Vibrating screen



Oct. 21,1930. J. WINSTON VIBRATING scnsnu 3 Sheets-Sheet 1 Filed June22, 1927 0a. 21;""193o, J. WINSTON 1,719,202

VIBRATING SCREEN Filed June 22, 1927 3 Sheets-Sheet 2 Filed June 22,1927 J. WINSTON \IVIBRA'IING sonar:

3 Shoetmoot 3 Qwwntot Patented Oct. 21, 1930 UNITED- STATES PATENTOFFICE nuns WINSTON, or onuqurcm'm, CHIL VIBRATING SCREEN Applicationfiled June 22, 1927. Serial No. 200,688.

screening material. 1

Another object of the invention is to provide a vibrating screen havinga side shake besides the usual up and down movement and constructed sothat the amplitude of vibration up and down and the amplitude of sideshake may be adjusted while the machine is in operation, such adjustmentrendering the machine efiicient in screening different classes ofmaterial.

A further object of the invention is to provide a vibrating screencapable of producing a violent stroke which will materially increase thescreening capacity of the machine.

A still further object of the invention is the provision of a vibratingscreen in which the screen is arranged at an angle and the vibrationtransmitted at or near the center of gravity of the screen when loaded,so as to produce uniform vibration of the entire screen area, relievingthe machine of unbalanced strain and permitting an economicalutilization of power. 7

As another objectof the invention I provide an anti-friction supportingmember for the screen during the vibrating thereof in order to relievestrain on the vibrator and mechanism for transmitting vibration to thescreen. i

I have for still another object of the invention the provision of springmeans for returning the vibration imparting mechanism besides springswhich support and return the screen, thus returning said mechanismimmediately after a stroke so that all strokes will be in a sudden,violent manner.

Also I have for an object to provide a flexible, resilient shaftcoupling between the power transmitting mechanism and the side shakerfor absorbing shocks from the side shaker and thus preventing the powermechanism from being subjected to such shocks.

It is also an object of the invention to provide a vibrator in which theamplitude of some vibrations are different from other vibrations, whichwill act as means for free,-

ing clogged meshes of the screen or for preventing them from clogging.

In carrying forward my invention, I also have for an object to providean adjustment for permitting the taking up of wear on the vibrator so asto permit the same amplitude of vibrations after the machine has beensubjected to continuous use.

Still another object of the invention is to provide adevice of the aboveindicated character, which is of a relatively simple nature, substantialin construction, which can be manufactured rather economicall and whichwill be thoroughly efiicient an practical in. use.

\Vith the foregoing and other objects in View, which will be apparent asthe description proceeds, the invention resides in the construction andarrangement of parts, as hereinafter described and claimed, it beingunderstood that changes can be made within the scope of what is claimed,without departing from the spirit of the invention.

In the accompanying drawings, forming a part of the specification,

Figure 1 is a vertical longitudinal section through my improvedvibrating screen,

I Figure 2 is a top plan thereof, showing a part of a casing removed,

Figure 3 is a side view of the vibrator,

Figure 4 isa section through the vibrator showing the main operatinmechanism,

. Figure 5 is a front elevatlon with the supporting structure removed,

Figure 6 is a detail section taken on line 66 of Figure 5 Figure 7 is af ra entary vertical section taken on line 77 o I igure 6,

Figure 8 is a side elevation of the flexible shaft coupling between thepower mechanism and side shaker lFigure 9 is an end elevation of saidooup er.

Referring to the drawings, the numeral 10 designates the base orsupporting structure for the screens which is constructed of angle ironto form a base section 11 and a vertical section 12 rising from the rearend thereof, said vertical section supporting from and be tween itsupper-end a pair of angle irons 13 inclined downwardly towards theforward end of the base structure and supported above the same b meansof bars 14 adjustably connected at t eir ends to the base 11 and angleirons 13, whereby the inclination of the latter may be changed asdesired, for which purpose the aforesaid supporting rods 14 are threadedat their ends and the blocks 15 to which they are connected are pivoted,at 16, to the base 11 and an le bars.

Supported from t e angle bars 13 is an inclined screen 19 restin at itsupper and lower ends on interpose coiled springs 17 the ends of whichare seated in cup-shaped members 18 secured to the angle bars and screenframe respectively. The screen frame is also constructed of angle barsand is disposed at the same inclination as the bars 13, said framehaving screening material 21 secured to the angle bars 20 forming thesame b attaching strips 22 under the latter and cfiimping the edges ofthe screening material between said strips and the undersurfaces of theangle bars. At each end of the screen frame and extending between theside pieces thereof are tension rods 23 having their op posite endsthreaded in blocks 24 secured to said side pieces. The tension rods haveright hand threads on one end and left hand threads on the other so thatby turning said rods in either direction the angle members 20 will bemoved towards or away from each other for tensioning the screen 21.

As the screen frame 19 is supported above the angle members 13 by meansof coil springs, anti-friction members 25 are rovided at the upper endsof the angle mem ers 13 for preventing longitudinal movement of thescreen frame, said anti-friction members consisting of short uprightbars 26 secured to the angle bars 13 and having rollers 27 at theirupper ends enga 'ng an angle member 28 extending across t screen framebetween the angle bars 20 thereof. It can be seen that when the screenframe is vibrated the angle member 28 enaging the rollers 27 will permitsaid screen frame to move in and up and down direction without danger ofIon itudinal movement thereof with relation to t e means supporting thesame.

The driving mechanism, hereinafter described, for operating the screenis mounted in a frame supported from the angle bars 13 and consisting ofuprights 29 secured at their lower ends to the outer sides \of saidangle bars and connected together at their upper ends by a cross piece30, the uprights and cross-piece being preferably formed of chan nelbars or plates. Mounted on the crosspiece intermediate its ends is acasing 31 in which is rotatably mounted a cam or tappetwheel 32 on ashaft 33 extending beyond the casing for attachment to an electric motor34 also mounted upon the cross-piece of the supe upper end of theporting frame. While I have shown an electric motor for operating thecam or tappetwheel it is to be understood that any type of power may besupplied to the shaft 33 for the purpose, said cam or tappet-wheelhaving tappets in the form of teeth 35 thereon adapted to strike one endof an arm 36 pivoted in the casing 31, as at 37 for causing said arm tobe swung on its pivot. The tappets 0r ratchet-teeth of the cam are ofdifferent lengths alternately so as to cause greater swinging movementof the arm 36 when engaged by one tooth than the other or adjacenttooth. The arm 36 has a spherical pivot member 38 confined in a bearingmember 39 at the upper end of a vertically reciprocating rod 40 whichextends downwardly to the screening frame through openings 41 in thecasing 31 and cross-piece 30 and at its lower end is provided with aclamping member 42 which engages about a tubular shaft or bar 43 carriedby the screen frame. The bar 43 has its opposite ends attached to theside pieces 20 of the screen frame and is attached thereto at a pointtowards the upper end thereof from the center of gravity or at thecenter of gravity of the screening frame when loaded with material to bescreened.

Extending through the casing 31 beneath the outer end of the arm 36 is ashaft 44 having a stop cam 45 thereon which is engaged by the arm 36after it has been swung on its pivot for limiting return movement ofsaid arm. It can be seen that when the shaft 44 is turned in the casing31 the return movement of the arm 36 may be adjusted so as to causegreater or less swinging movement thereof and thus regulate thereciprocating motion of the rod 40 which in turn will regu' late thevibrating of the screen. The shaft 44 is turned for changing theposition of the stop cam 45 by means of a crank handle 4647, the latterbeing held in adjustment by a series of depressions 48 in the side wallof the casing 31 with which a pin (not shown) on said crank handleengages. Cam 45 is of a sufficient size to hold the arm 36 out ofposition to be engaged by the teeth 35 of the ratchet or cam 32 when itis desired to stop the reciprocating of said rod 40 and vibrating of thescreen.

Attached to an intermediate portion of the reciprocating rod 40, as at49, is a leaf spring 50, which extends therefrom and engages the head 51of a depending bar 52 supported by a bracket 53 secured to the crosspiece 30 of the supporting frame at one side thereof, said depending barbeing provided at its upper end within a rectangular frame 54 in whichis a cam 55 mounted on a shaft'56 mounted in upstanding side pieces ofthe bracket 53. The shaft 56 has a crank arm 57 attached to the outerends thereof for turning the same in order to adjust the position of thecam 55 in the rectangular frame 54 so as to change positions of the head51 of the bar 52, thus changing the tension of the spring 50. In thebracket 53 are a series of depressions 58 into which the crank arm 57engages for holding the cam in adjusted position. The leaf springprovides the principal means for returning the arm 36 to its initialposition after being rocked by the teeth on the cam or tappet wheel 32as it returns the arm 36 to its position without depending on thesprings 17 which support the screen frame, thus providing a means forresetting the arm 36 immediately so that all strokes of thereciprocating rod 40 will be in a sudden, violent manner. By swingingthe cam 55 to a different position, the tension of the spring 50 may beregulated for causing proper returning of the arm 36.

The motor 34 has mounted on the rotary shaft 60 thereof a wheel 61provided with a pair of pins 62 extending from its face and adapted toengage yieldable leaf spring members 63 projecting from the periphery ofa collar 64 secured to a shaft 65 in alinement with the motor shaft. Theshaft 65 is mounted in a bearing 66 at the inner side of a casing 67mounted upon the cross piece adjacent one end thereof, and said shaftextends into the casing where it carries a cam 68 working in arectangular box-shaped frame 69 on one end of an arm 70 pivotallymounted in the casing by means of a pin 71. The arms 70 is slotted, asat 72, where the pin extends therethrough in order to permitlongitudinal movement .of said arm when swung on its pivot by rotationof the cam 68. To the end of the arm opposite the cam is pivotallyconnected the upper end of a rod 73 which extends through a bearing 75in the casing 67 and through the cross piece 30 which supports saidcasing. The rod 73 extends downwardly adjacent one of the u rights ofthe supporting frame and is sli dably mounted in a bearing 76 secured tosaid upright. On the lower end of the rod 73 is a laterally extendingpin 77 which extends into a slot 78 in one side of a collar 79 mountedin a bracket 80 for turning movement, said bracket 80 being secured toone of the angle bars 20 of the screenin frame. The collar 79 is on ashort sha t 81 which extends through the bracket 80 and is provided atits outer end with a crank arm 82, and on the adjacent side of thebracket 80 are a series of indentations 83 into which a projecting pinon said crank arm is adapted to engage for holding the collar 79 inadjusted position. It can be seen that by turning the crank, theposition of the slot 78 in the collar maybe changed. By changing theangle of the slot the side shaking of the screening frame will beregulated, as reciprocating motion of the rod 73 causes the screeningframe to be moved sideways due to the fact that the bin 77 carriedthereby is arranged in an angularly extending slot.

porte In operation, the electric motor 34 will rotate the shaft 33causing the cam or tappet wheel 32 to be rotated in the directionindicated by the arrow in Figure 4 of the drawings. Upon such rotationof the wheel the teeth thereof will engage one end of the arm 36swinging the same on its pivot, thus imparting a sudden, violent upwardmovement to the screening frame, due to the fact that the rod isconnected to the arm 36 and to the screening frame. It is to be noted byreferring to Figure 4 of the drawings that four teeth are provided onthe cam or tappet wheel 32, two of one size and the other two of alarger or smaller size and that the teeth alternate in size around theperiphery ofthe wheel, thus causing the amplitude of some vibrations tobe different from other vibrations. The result obtained is similar tothat obtained by an outside blow for freeing clogged meshes of thescreen or preventing them from clo ging. While I have shown four teethon t e cam or tappet wheel it is to be understood that any number ofteeth of different sizes may be provided and the relative arrangementthereof modified, it being my idea to provide a vibrator in which theamplitude of some vibrations is different from others. By adjusting theposition of the stop cam 45, the amplitude of all vibrations is changed,thus providing a means whereby the amplitude of vibrations may beincreased or decreased according to the material being screened. The topcam also provides means for taking up wear on the vibrator arm 36 andtappet or cam 32 after the same have been subjected to considerable use.

It can be seen that when a'tooth 35 on the cam or tappet strikes the endof the arm 36,

said arm acquires a sudden, violent and positive motion which will causeeflicient 'screen-.

ing of material on the screen frame, due to the fact that the other endof the arm 36 connected to rod 40 acquires a motion of the samecharacteristics but in an opposite direction. The return movement of thearm is effected by the leaf spring so as to immediately return the armto a position to be engaged by the next tooth on the cam or tappet 32.The tension of the leaf spring may be varied by turning the cam in therectangular frame so as to raise or lower the bar 52 which the spring 50engages.

Operation of the motor 34 will also cause the shaft to be rotated as itis connected to the motor through a flexible coupling and upon rotationof this shaft, the arm will be rocked causing the rod 73 to bereciprocated. Upon reciprocating motion of the rod 73 the pin 77 thereonwill cause the screen frame to be moved sideways due to the fact thatthe slot 78 in the collar 79 is arranged at an angle and the fact thatthe rod 53 is supby bearings and is not permitted to swing to the side,thus causing a side shaking motion to the screening frame. The sideshaking mechanism imparts to the screen a vibration erpendicular to thatproduced by what migiit be called the primary vibrator above described.When the collar 79 is arranged so that the angle thereof is parallelwith the reciprocatingmovement of the transmitter rod 73, the pin 77reciprocates in the slot 78 without imparting any side shake to thescreen, thus permitting the side shake of the machine to cease duringoperation of the machine. When the collar 79 is turned so that the slottherein is at an angle with relation to the movement of the rod 73,there is a sidewise movement imparted to the screen as the rod 73 isheld against side movement. It is to be noted that this movement isatboth sides of the normal position of the screen and that the sideshaking mechanism greatly increases the efiiciency and capacity of thescreen, as it increases the path of movement of articles which travelover the screen.

y providing a resilient, flexible shaft couplin between the motor andthe side shaker, shoc s are absorbed from the side shaker or secondaryvibrator, thus relieving strain on the motor. By providing springs 63 inthe resilient, flexible coupler, the same act as cantilever sprin s andare engaged by the pins or lugs 62 in orming the driving connection. Onthe pins 62 are leather or other nonmetallic sleeves to prevent a metalto metal contact, thus obviating the need of lubrication.

When it is desired to tighten the screening material or when a wornscreen is replaced by a new one, the bars 23 are rotated y means of anyap roved wrench so as to cause the oppositely t readed ends of said barto turn in the blocks 24 for moving the angle bars 20 having the screenmaterial attached thereto away from each other.

The reciprocating rod 40 is attached to the screen frame 19 between thecenter line of the screen and the feed end thereof, the object being toform a connection to the screen at the center of gravity of the screenwhen loaded, as there is more material on the screen at the upper orfeed end than at the lower or discharge end for some of the materialpasses through the screen on its way down, consequently this arrangementwill provide a more uniform vibration of the entire screen area, lesseccentric, relieves an unbalanced strain on the machine, and produces amore economical utilizatlon of power.

By providing the anti-friction mechanism at the upper end of thescreening frame the latter is held against tendency to move downwardsduring operation, thus relieving the reciprocating rod or transmitter 40from strain of such movement. The ball bearing against the angle member28 will also permit side movement of the screening frame by thesupplemental vibrator or side shaker. The springs 17 which support theweight of the screen are arranged in such a manner that the vibratorfurnishes power only for vibrating the screen and is relieved fromcarrying dead weight.

It is to be noted that I have provided adjustments for the amplitude ofvibrations of the primary vibrator, for the amplitude of vibrations ofthe side shaker, and for the tensioning of the spring that returns thepri-.

mary vibrator mechanism, by means of crank arms which may be simplyturned to known positions for obtaining different adjustments, therebyobviating the use of tools for such work and permitting the properadjustment without experimenting with same.

Having thus described my invention, what I claim as new is:

1. A vibrating screen for the purposes set forth comprising a supportingframe, an inclined screen yieldably supported in said frame for verticaland lateral vibrations, an auxiliary supporting frame overlying thescreen and having a cross-piece at its upper end, a motor mounted on thecross-piece and having a driving shaft projecting at opposite sides,means for imparting a vertical vibratory motion to the screen operatedby the shaft at one side of the motor, and means for imparting a lateralvibration to the screen operated by the shaft at the other side of themotor.

2. A vibrating screen for the purposes set forth comprising a supportingframe, an iIi-' chned screen yieldably supported in said frame forvertical and lateral vibrations, an auxlhary supporting frame overlyingthe screen and having a cross-piece at its upper end, a motor mounted onsaid crossplece and having a driving shaft projecting at opposite sidesthereof, a tappet-wheel keyed to the shaft at one side'of the motor andoperating a lever connected to the screen for imparting a verticalvibration thereto, a wheel carried by the shaft at the other side of themotor and having outwardly projecting pins, and means for impartinglateral vibrations to the screen and having yieldable members engaged bysaid pins for operating said vibrating means.

3. A vibrating screen comprising a supporting frame, an inclined screenmounted therein for vertical vibrations, a supporting frame for thevibrating mechanism attached to the aforesaid supporting frame andoverlying the screen, a tappet-wheel and means for operating the samesupported on said last mentioned supporting frame, and a pivoted leverwith which the tappet-wheel engages at one end, and a rod pivoted to thelever at the other side of its pivot and connected to the screen;together with means adapted to engage the outer end of the lever forholding it out of operation with respect to the tappetwheel.

4. A vibrating screen for the purposes set forth comprising a supportingframe, an inclined screen yieldably supported on said frame for verticaland lateral vibrations, an auxiliary supporting frame overlying thescreen and-having a crosspiece at its upper end, a motor mounted on thecross-- piece and having a drivin shaft, means operated by the drivingsha t forimparting a vertical vibratory motion to the screen, and meansoperated by the shaft for imparting a lateral vibration to the screen;together with a plate extending across the underside of the inclinedscreen, and an arm projecting from the supporting frame andearing'against the plate to oppose downward movement of said screen.

5. A vibrating screen for the purposes set forth comprising a supportingframe, an inclined screen yieldably supported on said frame for verticaland lateral vibrations, an auxiliary supporting frame overlying thescreen and having a crosspiece at its upper end, a motor mounted on thecrosspiece and having a drivin shaft, means operated by the driving shat for imparting a vertical vibratory motion to the screen, and meansoperated by the shaft for imparting a lateral vibration to the screen;together with a plate extending across the underside of the inclinedscreen,'an arm projecting from the supporting frame to cooperate withsaid plate for opposing downward movement of the screen, and a ballbearing interposed between the arm and plate to freely, permit of thevibratory motions ofsaid screen.

6. A device of the character described comprising a frame, an inclinedscreen loosely supported therein, spring means for yieldably supportingsaid screen by said frame, means for imparting vibration to said screen,an angle plate carried by said screen, an upright carried by said frameand hav-' ing a roller bearing engaging said plate for preventinglongitudinal movement of said screen with relation to said frame.

In testimony whereof, I have afiixed my iignature.

JAMES WINSTON.

